Effect of postoperative radiation therapy on mandibular reconstruction using a modular endoprosthesis - a pilot study

Area of Science:

• Oral and Maxillofacial Surgery
• Biomaterials Science
• Radiation Oncology

Background:

• Mandibular reconstruction often requires complex surgical interventions.
• Endoprosthetic systems offer a potential solution for mandibular defects.
• The impact of adjuvant radiation therapy on these reconstructions is not fully understood.

Purpose of the Study:

• To evaluate the effects of postoperative brachytherapy on bone and soft tissue healing in Macaca fascicularis mandibles reconstructed with cemented endoprostheses.

Main Methods:

• Six Macaca fascicularis mandibles underwent segmental resection and reconstruction with cemented endoprostheses.
• Animals were divided into a test group (received brachytherapy 1 month postoperation) and a control group (no radiation).
• Bone healing was assessed using Micro-CT for total bone volume percentage (TBV%), and soft tissue response was evaluated via histomorphometrical analysis and clinical observation.

Main Results:

• No significant differences in TBV% were observed between the radiated and control groups.
• Histomorphometrical analysis showed no significant differences in tissue response.
• Minor side effects like mucosal ulcerations in the radiated group healed within 4 weeks; prosthesis failure occurred in one animal from each group.

Conclusions:

• Postoperative brachytherapy, under the study conditions, did not adversely affect early bone and soft tissue healing around mandibular endoprostheses.
• The endoprosthetic system remains a viable option for mandibular reconstruction in patients requiring postoperative radiation.